Hyperpolarization-activated cyclic nucleotide-gated 2 contributes to electroacupuncture analgesia on lumbar disc herniation-induced radicular pain through activation of microglia in spinal dorsal horn.

OBJECTIVE: To explore the mechanisms of dorsal root ganglia and spinal microglia cascade cross in electroacupuncture (EA) analgesia in the treatment of lumbar disc herniation. METHODS: A rat model of lumbar disc herniation (LDH) was established, EA was administered at Huantiao (GB30) acupoint 30 min once a day, for 3 d. Before and after modeling, and after EA, mechanical allodynia thresholds were detected. Hyperpolarization-activated cyclic nucleotide-gated 2 (HCN2) in dorsal root ganglia was detected by quantitative polymerase chain reaction (qPCR) and Western blot. C-X3-C motif chemokine ligand 1 (CX3CL1) and activity of microglia in spinal cord was observed separately qPCR and immunofluorescence staining. RESULTS: The mechanical allodynia threshold of the right planta of model rats was significantly reduced ( < 0.01), EA increased the mechanical pain threshold of rats ( < 0.01), and decreased HCN2 mRNA, and protein expression, reduced the expression of CX3CL1 and the activation of microglia. ZD7288 (a blocker of HCN channel) reduced the analgesic effect of EA from 1.83 ± 0.84 to 0.74 ± 0.20 ( < 0.05), and the expression of CX3CL1 in the spinal cord decreased from 0.52 ± 0.11 to 0.15 ± 0.05 ( < 0.01). CONCLUSION: EA analgesia on the radicular pain of LDH is definite. EA reduced the expression of HCN2 channel in the dorsal root ganglion, thereby decreasing the noxious stimulation entered to microglia in spinal dorsal horn. Our work supports EA is an effective treatment for radicular pain of LDH.

Effect of manual acupuncture on bowel motility in normal kunming mouse.

OBJECTIVE: To observe the effects of acupuncture on motility of jejunum and distal colon at different acupoints on normal Kunming mice. METHODS: The jejunal and colorectal motor activity of forty Kunming mice were recorded by the intra-intestinal capsule. The capsules contained with distilled water were placed into the cavities of jejunum and distal colon. The changes of bowel were compared with the background activity recorded before any stimulation. The chosen acupoints were as follows: Zusanli (ST 36) on the lower legs, Tianshu (ST 25) on the mid-lower abdomen. RESULTS: Manual acupuncture (MA) at Zusanli (ST 36) significantly promoted the motility of jejunum and distal colon (manifested as increased change rate of average amplitude and increased change rate of mean area under the contractile curve) of normal Kunming mice (P < 0.01). MA at Tianshu (ST 25) significantly inhibited the motility of jejunum (manifested as decreased change rate of average amplitude, decreased change rate of mean area under the contractile curve, and the reduced frequency) of normal Kunming mice (P < 0.01), while significantly increased the distal colonic motility (manifested as increased amplitude and increased mean area under the contractile curve) of normal Kunming mice (P < 0.01). CONCLUSION: MA at specific acupoints [Zusanli (ST 36), Tianshu (ST 25)] has different effects on the motility of jejunum and distal colon, which might involve the segmental innervations of the related nerve.